Some cities in the U.S. are seeing their air quality suffer due to smoke from Canadian wildfires.

Heavy smoke from several large wildfires blazing in Canada and Minnesota engulfed large swaths of the Midwest and East Coast.

Smoke from wildfires in Canada is pouring into the US and will usher in unhealthy air quality for millions of people in Northeast and Midwest.

A National Weather Service meteorologist said even if winds from the northwest clear skies as expected later this week, the smoky air could keep returning until the fires are out. That could take ...